Difference between revisions of "ApCoCoA-1:CharP.GBasisF2048"

From ApCoCoAWiki
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<itemize>
 
<itemize>
<item>@param <em>Ideal</em> An Ideal in a Ring over Z, where the elements 0,...,2047 represent the field's elements. For short, the binary representation of the number represents the coefficient vector if the polynomial in the field, e.g. 11 = 8 + 2 + 1 = 2^3 + 2^1 + 2^0. So the number 11 corresponds to the polynomial x^3 + x + 1.</item>
+
<item>@param <em>Ideal</em> An Ideal in a Ring over Z, where the elements 0,...,2047 represent the elements of the field F_2048. For short, the binary representation of the number represents the coefficient vector if the polynomial in the field, e.g. 11 = 8 + 2 + 1 = 2^3 + 2^1 + 2^0. So the number 11 corresponds to the polynomial x^3 + x + 1.</item>
 
<item>@return A Groebner Basis of the given ideal.</item>
 
<item>@return A Groebner Basis of the given ideal.</item>
 
</itemize>
 
</itemize>
 +
 +
<example>
 +
Use R::=QQ[x,y,z];
 +
I:=Ideal(x-y^2,x^2+xy,y^3);
 +
GBasis(I);
 +
 +
[x^2 + xy, -y^2 + x, -xy]
 +
-------------------------------
 +
Use Z::=ZZ[x,y,z];
 +
-- WARNING: Coeffs are not in a field
 +
-- GBasis-related computations could fail to terminate or be wrong
 +
 +
-------------------------------
 +
I:=Ideal(x-y^2,x^2+xy,y^3);
 +
Char2.GBasisF2048(I);
 +
-- WARNING: Coeffs are not in a field
 +
-- GBasis-related computations could fail to terminate or be wrong
 +
-- CoCoAServer: computing Cpu Time = 0
 +
-------------------------------
 +
[y^2 + 1205x, x^2, xy]
 +
-------------------------------
 +
</example>
 +
 
     </description>
 
     </description>
  

Revision as of 07:37, 14 July 2009

Char2.GBasisF2048

Computing a Groebner Basis of a given ideal in F_2048.

Syntax

Char2.GBasisF2048(Ideal:IDEAL):LIST

Description

Please note: The function(s) explained on this page is/are using the ApCoCoAServer. You will have to start the ApCoCoAServer in order to use it/them.

This command computes a Groebner basis in the field F_2048 = (Z/(2))[x]/(x^11 +x^3 + x^5 +x + 1).

  • @param Ideal An Ideal in a Ring over Z, where the elements 0,...,2047 represent the elements of the field F_2048. For short, the binary representation of the number represents the coefficient vector if the polynomial in the field, e.g. 11 = 8 + 2 + 1 = 2^3 + 2^1 + 2^0. So the number 11 corresponds to the polynomial x^3 + x + 1.

  • @return A Groebner Basis of the given ideal.

Example

Use R::=QQ[x,y,z];
I:=Ideal(x-y^2,x^2+xy,y^3);
GBasis(I);

[x^2 + xy, -y^2 + x, -xy]
-------------------------------
Use Z::=ZZ[x,y,z];
-- WARNING: Coeffs are not in a field
-- GBasis-related computations could fail to terminate or be wrong

-------------------------------
I:=Ideal(x-y^2,x^2+xy,y^3);
Char2.GBasisF2048(I);
-- WARNING: Coeffs are not in a field
-- GBasis-related computations could fail to terminate or be wrong
-- CoCoAServer: computing Cpu Time = 0
-------------------------------
[y^2 + 1205x, x^2, xy]
-------------------------------


See also

GBasis

Introduction to CoCoAServer

Introduction to Groebner Basis in CoCoA

Char2.GBasisF2

Char2.GBasisF4

Char2.GBasisF8

Char2.GBasisF16

Char2.GBasisF32

Char2.GBasisF64

Char2.GBasisF128

Char2.GBasisF256

Char2.GBasisF512

Char2.GBasisF1024

Char2.GBasisF4096

Char2.GBasisModSquares

Representation of finite fields